Plaintiffs of the kids’ climate change case and supporters rally in San Francisco in December 2017.

The Supreme Court on Friday rejected a Trump administration request to prevent a trial in a high-profile lawsuit in which a group of young people are trying to force the federal government to take broad action on climate change, claiming it hasn’t done enough to ensure their right to a safe and clean environment.

The high court, however, strongly suggested that further questions should be resolved by the appeals courts before the case goes to trial.

The Justice Department had asked the Supreme Court in late October to order a halt to the trial, which had been scheduled to begin on Oct. 29. The court denied that request — but it did so “because adequate relief may be available in the United States Court of Appeals for the Ninth Circuit.”

In a three-page, unsigned order, the Supreme Court suggested that an immediate appeal of the district court’s ruling on key legal questions is likely appropriate before any trial begins.

For now, though, the temporary stay on the trial, which had been issued by Chief Justice John Roberts while the court considered the Trump administration’s request, has been lifted, with justices Clarence Thomas and Neil Gorsuch stating that they would have granted the request.

The mixed-bag ruling is just the latest winding development in the three-year-old case.

The group of 21 plaintiffs, a mix of minors and young adults from across the US, filed the lawsuit in 2015, alleging the federal government was contributing to climate change in violation of their constitutional rights to life, liberty, and property.

Over the summer, the Justice Department had asked the Supreme Court to stop the case, but it declined to do so at that time, calling the request premature. However, the court noted that “[t]he breadth of [the plaintiffs]’ claims is striking ... and the justiciability of those claims presents substantial grounds for difference of opinion.” The Supreme Court told the district court to “take these concerns into account” moving forward.

In mid-October, US District Judge Ann Aiken ruled on the final set of the government’s key motions before trial, narrowing the case further — including by dismissing President Trump as a defendant — but allowing the majority of the case to proceed to trial. At that time, she also denied the government’s request for interlocutory appeal — which allows for immediate appeal of a particular legal issue before it would normally be heard on appeal after a final ruling in a case.

In Friday night’s order from the Supreme Court, justices strongly questioned the decision not to allow an immediate appeal, noting its earlier language from the July order that the claims in the case present “substantial grounds for difference of opinion,” and pointing out that the standard under which a judge can allow for interlocutory appeal is when an order addresses “a controlling question of law as to which there is substantial ground for difference of opinion” and where an immediate appeal could shorten the length of the litigation.

“Presumably the government will now file an emergency motion with the 9th Circuit, requesting a stay of the trial pending an appeal of the motion for summary judgment,” Michael Burger, the executive director of Columbia’s Sabin Center for Climate Change Law, told BuzzFeed News.

Our Children’s Trust, the group representing the plaintiffs, told BuzzFeed News that before the government’s stay request, the witness list was set, three depositions were left, and pre-trial motions awaited action.

Despite the ins and outs of Friday’s order, until a court rules otherwise, the lawyers for the plaintiffs are going with a “full steam ahead” approach. The lead lawyer, Julia Olson, said in a statement that they have asked the district court “for an immediate status conference to get Juliana v. U.S. back on track for trial in the next week.”